Shock absorber



P.HANFORD SHOCK ABSORBER Feb. 16 1926. 1,573,058

Filed July 14' 1919 4 2 Sheets-Sheet l Feb. 16 1926. 1,573,058

I P. HANFoRD SHOCK ABS ORBER Filed July 14l 1919 2 sheets-sheet 2 A a flPatented Feb. 16, -1926,

Unirse PEMLYHANFEZD,

ABSCDRBER.

Application died "ul'j le, 193.9. `Serial @10,71%

To all whom t may concern:

Be it known that I, PARMLY Harmonie, a citizen -oi'f the United States,residing at Springield, in the county of vHampden, State ofMassachusetts, .have invented certain new and useful Improvements ShockAbsorbers, of which the foliowinrf is a description, reference being hadto the accompanying drawing and to the figures of reference markedthereon,

This invention relates to shock absorbers for motor vehicles.

The object of the invention is to provide a shock absorber whichnormally allows the springs free action regardless of whether they areexpanding or contracting, and which only comes into action when thechassis rises suddenly from its plane of travel, at which time itfunctions to prevent l the springs from expanding too quickly.

Referring more particularly to the draw@ ings- Figure 1 is an elevationof one form of my device, the connection to the chassis being omitted;

Figure 2 is a modilication thereof;

Figure 3 is still anotherembodiment; and

Figure 4 is a sectional view thereof, taken through the line 4 4, i

One form of the invention lconsists of a friction drum rotatably mountedon the chassis of the vehicle and provided with a connection to theaxle, whereby, as the axle approaches the chassis, the drum is rotatedEither externally or internally mounted on or in said drum is airietionstrap having one end thereof fast to the chassis and the other end adated to be operated by one end of a lever, li ewis'e pivoted to thechassis, so that movement of said lever in the proper ydirectionoperates to tighten the strap on the drum. Mounted preferably adjustablyof the strap on the free end of the lever, is a weight which normallymoves with the lever and the chassis, but which, due to its inertia andits suspended position on said lever, operates said lever upon theoccurrence of any sudden upward movement of the chassis.

In another form the invention includes a cylinder attached to thechassis and a piston reciprocable therein, the free end of which isconnected with the axle. Between the piston and the bottom of thecylinder there is provided a, braking fluid with p orts in the bottomwalls of said cylinder to provide for the escape of said tiuid wherebysaid piston may approach the bottom of said cyiinder. lliocate'dnormally above said ports andy suspended in such position from thecylinder c v which norm reciprocates `with the cylinder when chassismoves, but which, due to its inertia and the suspension thereof from thecylinder, permits a relative movement between it and the cylinder,thereby operatingP tociose the ports in the cylinder g by a spring, is aweight to check the movement ofthe piston therein,

so that the chassis can not spring upwardly suddenly. y

Referring new more particularly to Figure 2, there is provideda movablemeniber in the `form of a cylindrical drum 1, rot-atively mounted on theshaft 2, fixed to the chassis 3 of the vehicle. In order to cdnnect thisdrum. 1 with the axle 4, there is provided a rod 5 pivotedto the drum,as at 6, and connected to the axle in any suitable manner. A braking orretarding member for the drum 1 is provided in the shape of a frictionlstrap 8, one end 9 of which is pivoted to the chassis, as at 10, andthe other end 11 to the end 11 of a lever 12 pivoted at 13 to thechassis. On the other end of the lever weight 13.

-In operation, when the vehicle wheels encounter small inequalities inthe road, `the up and down movement of the chassis is not sudden enoughtocause relative movement of the weightedt arm or lever 12, so theweight 13 will move with 'the chassis 3, but when a sudden jolt occursthe springs in expandingI rapidly will cause a quick upward movement of'the chassisz, on which is mounted the lever 12, and by reason of thesuspended position lof 'the weight 13 and the inertia thereof, it willact to depress the vlever'12 and force the free end 11 to tighten thestrap 8 on the drum 1, thus checking the rotation of the drum andlikewise the movement of the chassis away from the axle.

In 'the form disclosed in Figure 1 the outer portion of the drum hasbeen removed,

leaving only the drum rim 1 and thejourll2 is slidably mounted the1 end16 attached to the chassis as at 18, and the other end 19 within thepath of movement of the weighted lever 20, which is likewise mountedwithin the drum 1 and pivoted to the chassis, as at 21. One end 22- ofthe lever 2O `is curved about the shaft (likewise mounted on thechassis) and lprovided with a weight 23 on its extreme end, while theother end 24 thereof is provided with a nose 25 to engage the free end19 of they expanding strap 15. In order to sup ort the weight 23 in itsnormal position an to prevent the strap from rubbing against the drum 1,there is provided the suspension spring 2d having one end attached tothe;

strap and the other end to the weight. The curvilinear shape of thelever arm is merely for the.. purpose of providing a compact arrangementReferring to the modication shown in Figures 3 and e, the chassis 3 isprovided with a verticallyI located cylinder having an inner cylindricalpiston chamber 26, between the walls 27 ofwhich and the walls of thecylinder 25 is located an annular chamber 29. Near the bottom, the walls27 of the inner piston chamber 26 are provided 555 said chamber 29. Nearthe 'and figuration to act ports. This'vveight is adapted to be held inVwith one or more ports 28 connecting said piston chamber with theannular surrounding chamber 29. Located within the-piston chamber 26 isa piston 30 provided with a rod 31 passing through a suitable packing 32at one end or the cylinder and adaptekl to be connected to the axle. lnordeA provide a braking eect between the cin-n der 25 and piston 30,there is introduced intoihe piston chamber a iiuid medium in the horno.ont oil or an other suitable liquid, normally, this oil is capable ofpassing freely through the orts 28 inthe walls`2?7 of the piston cham er26 into the annular surrounding' chamber 29. For the purpose ofcontrolling these ports 28, there is located, preferably in this outerchamber 29, an annular weight 32" oit suitable shape'and conas a closingvalve for the suspended position above t e ports by means of a spring 35attached at the lower end of thef'weight, 'as at 3d, and at its upperend tothe top of the cylinder casing, as at 35'..

To limit the extreme upper movement of the weight in said chamber thereis preferably provided a lug 36 on the interior wall of to ci the wall27 of the iston chamber 26 is coated a port 37 throng which any oilescaping past the oiston may return to the outer chamber 29. "i is portalso serves to equalize the pressure inthe inner and outer chambers.

In operation a sudden upward movement of the chassis 3 will cause theweight 32 t take the position shown in dotted lines, thereby closing theports 28 and preventing the sudden escape of the fluid, so that'therelative movement between the piston 30 and the cylinder 25 is checked.AS in this prior construction, this relative movement between the weightand the cylinder (attached to the chassis 3) is due to the inertia ofthe weight and its suspended position on the Chamis.

While this action is produced by a sudden upward movement of thechassis, on the other hand, any gradual or slight move- `'ment of thechassis in either direction'will 1. A shock absorber for motor vehiclesincluding a friction drum connected'to the chassis and axle whereby saiddrum is operated by the relative movement between said drum and axle, afriction strap operatively arranged with respect to the drum, avertically movable Weight, and connections from i said weightto saidstrap to operate the latter upon the occasion of a sudden movement ofsaid chassis.

2. A shock absorber for motor vehicles comprising a friction drummounted on the chassis, an arm pivoted to said drum and connected to theaxle, a friction band engaging said drum, one end of said band beingfixed to the chassis, a weighted lever pivoted to said chassis andcapable of movement about its y pivot due to, the inertia of the weightthereof upon a sudden movement of said chassis for operating saidfriction band. Y, 3. ln a device of the character set. forth, anoscillating drum actuated by a proach or separation of axle and chassis,a braking device to retard the oscillation of said drum `and an inertiameans to cause said braking device to -act said drum.

d. In a device of the character set "forth, an oscillating drum actuatedby approach and separation of axle and chassis, a restraining device andmeans to cause said restraining device to act upon said drum withdifferential forces depending upon the with varying pressures onrelations existing between the vertlcal ac-y celeration of the chassisand movements of approach or recession betweenl the chassis and axle.

5. ln a device of the character set forth, a movable drum, ineens tocommunicate vertical movement of an axle to said drum to oscillate it, abrake band about the drum,

and inertia-means tol contract thc brake band said inertia meansoperating upon saidA brake band with varying pressures.

6. In a shock vabsorber for vehicles, a balanced actuating member, andmeans to restrain relative movement of chassis and axle of the vehicleoperated upon displacement oi' said actuating member 'from its normalbalanced posltion, said restraining means comprising a brake band and anos.

' balanced weight and means to restrain relative movement of chassis andaxle of the vehicle operated upon displacement of said Weight from itsnormal balanced position, said restraining means comprising a brakeband, and a brake drum, and means to cause said brake band to Wrap up onthe drum.

8. In a shock absorber for vehicles, a balanced Weight and means torestrain relative movement of the chassis and axle of the vehicleoperated upon displacement of said Weight from its normal balancedposition, said restraining means comprising a brake band and a brakedrum, said drum being mounted to oscillate upon relative movement ofchassis and axle, and a lever connected to said Weight, said leverbearing against the brake band.

9. In a shock absorber for vehicles, a balanced weight and means torestrain relative movement of the chassis and axle of the vehicleoperated upon displacement of said weight from its normal balancedposition, said restraining means comprising a brake band and a brakedrum, said drum being mounted to oscillate upon relative movement ofchassis and axle, a lever connected to said weight, said lever bearingagainst the brake band, and an abutment in the path of the brake band toprevent its rotation with the brake drum.

10. In a shock absorber for vehicles, a

brake drum oscillated4 upon relative movement of the chassis and axle, asplit brake band surrounding 'said drum and moans to cause said brakeband to restrain the oscillations of said drum, said means comprising aninertia vveight anfL a lever to contract said band, and means to causesaid band to Wrap itself upon said drum.

11. In a shock absorber for vehicles, a brake drum oscillated uponrelative movement of the chassis land axle, a split brake bandsurrounding said drum, and means to cause said brake band to restrainthe oscillations of said drum, said means comprising an inertia Weightand a lever connected therewith to contract the band, and an abutment inthe path of the band to prevent its movement with the drum.

12. In a shock absorber adapt-ed to control the motion of a springmounted body, a balanced actuating member, Vand means torestrainmovement of the body relative to its support operated upondisplacement of the actuating member from its normal balanced position,said restraining means comprising a brak-e band and an oscillatory drumwith which said brake band contacts.

13. In a shock absorber adapted to control the motion of a vspringmounted body, a balanced actuating member, and mcans'to restrainmovement of the body relative to its support operated upon displacementof the actuating member from its normal balanced position, saidrestraining means comprising a brake band and an oscillatory drumenclosed bythe brake band, and connections from t-he body and theactuating member to the band and the drum to oscillate the drum andcontract the band.

' In testimony whereof, I ajlix my signature.

PARMLY 'HANFoRn 'nsA

